Tsunami deposits of the 2011 Tohoku earthquake and the 869 Jogan earthquake

The 2011 Tohoku earthquake caused enormous tsunami damages to an extensive area of the Pacific coast of eastern Japan. This is a peeled cross section of strata beneath the Sendai Plain that was taken after the earthquake using the Geoslicer technique. The ground surface is covered with the tsunami deposit from the Tohoku earthquake. The sand layer between the two black peat layers is also a tsunami deposit. Volcanic ash immediately above it is identified as being from the 915 eruption of the Towada volcano. Taking this into account, together with the results from dating the peat layer beneath it, this tsunami deposit is thought to be from the 869 Jogan earthquake, which is documented in "Nihon Sandai Jitsuroku," one of the ancient writings of Japan.